This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This study was conducted to determine whether an immune response would be elicited to RBCs treated with the Mirasol pathogen reduction technology (MPRT) using Riboflavin and UV light. The second objective was to assess the survival and recovery of MPRT treated RBCs in baboons. Autologous RBC's either untreated or Mirasol-treated were formulated with alum adjuvant and was injected into the respective baboon donors. No antibody response to RBCs was observed either in the untreated or MPRT treated baboons. Next, untreated and MPRT treated RBCs were labeled with CR51 and infused back into the donors. Survival and recovery kinetics were quite similar in the untreated and MPRT treated baboons.